23 Quite clearly, the extent of the allowance for past and/or future co-operation depends upon the nature of the crime and the quality of the assistance. The appellant submits that as a matter of public policy the offer to assist authorities ought be given great weight in mitigation of sentence and attract a substantial discount. In this regard, counsel for the appellant relies upon R v McMahon[22]. That case is authority for the proposition that the 'discount appropriate to be given to a true informer will always be considerable'[23]. However, in the circumstances before us, the appellant can hardly be seen to be in the category of an informer who, at considerable risk, rendered very valuable services to police vis-à-vis the community.[24] The circumstance before us is that the appellant, when interviewed, lied to the police as to his and his co-accused's part in the offences. By contrast, the prosecution's opening statement upon the plea records that the two co-offenders were arrested and interviewed on 7 July 2005 and made full admissions in relation to these offences. It was later that day that the appellant was arrested and interviewed. However, on 2 November 2006, the appellant made a statement to police whereby he accepted his responsibility for the offences and implicated the two women as co-offenders. It would appear that at the time of the appellant's plea and sentence the co-offenders were intending to defend the charges which had been laid against them. Accordingly, his undertaking to the court was that he, as the principal offender, would give evidence against his co-offenders if called upon to do so. However, as the sentencing judge observed, the value of the appellant's undertaking was required to be assessed in the context of the brazen lies told to police by him in the course of his interview. As is submitted by the respondent in written submissions, clearly those lies would be used against the appellant in any trial to contradict the evidence he gave in accordance with his statement. Furthermore, as stated by Phillips CJ in R v Nguyen[25], the weight to be given to the appellant's co-operation has to be 'balanced against other considerations, including the seriousness of the appellant's major offence and its circumstances of aggravation'. In this case, the appellant's part in the major offence of engaging in reckless conduct endangering life was as the principal offender. It was he who recruited his co-offenders to assist him. It was he who drove to the complainant's home on two occasions. It was he who possessed the handgun, and it was he who used it. In my view, the value of the appellant's offer to give evidence against his co-offenders has to be considered in the light of such circumstances. Furthermore, it is apparent from the authorities that there is no such thing as a standard informer discount[26]. In my view, in all the particular circumstances of this case, the sentencing judge cannot be said to have given insufficient weight to the undertaking of the appellant to give evidence.